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Support Forum » Still on first part. LCD showing strange lines.

January 02, 2012
by Anirudha
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Hey guys, I had blown up a MCU earlier. So I bought another one but after like 6 months (overseas :-( ). My guess is LCD is damaged. I had done some mistakes where regulator was heating up. Fixed that, and and checked if i blew up regualtor, i did not. I have attached images. After a couple of secs the the lines fade away.

Alt Text Alt Text Alt Text

January 02, 2012
by Anirudha
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I had bought one MCU extra just in case. Put that one up too. Got the same result. Bought both the MCUs from the store page. Both are Atmel168

January 02, 2012
by Rick_S
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From you photo's it's hard to really tell what is going on. I can't see the LCD wiring good enough to determine if it's wired correctly or not.

What problem did you have initially that overheated your regulator? What problem did you have months ago that damaged the MCU and was the LCD hooked up then?

Rick

January 02, 2012
by Anirudha
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I am pasting one more pic.

As the troubleshooting said, if I might have shorted + and - poles, then it might get hot. It might have blew up even this MCU but, after fixing the connecttions as I said above I tried with one more MCU. Still the same fault.

Long ago a lot of connections I did were totally wrong, and that blew up the MCU, but the LCD worked then, cause it showed 1st and 3rd rows lit up.

I know the pic is not that sharp but try making out the numbers. alt text

January 02, 2012
by Anirudha
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Ok, now I am pretty sure the LCD is gone. For one reason, I removed all the data pins and lets the power pins remain. Same fault. Now my question is, is this LCD preconfigured, cause I am thinking of picking it up from a nearby store.

January 02, 2012
by Rick_S
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There is no configuration on the LCD, It uses a pretty standard controll chipset that most common LCD's use. Even the pinout is the same on Most - NOT ALL though so be sure before wiring.

Also, I see a yellow wire that appears to be in the crystals row. There should be no wire there. It's really hard to tell. Can you get closeups of the LCD side of the breadboard from a couple of different angles?

These parts are pretty resiliant and while they can be damaged, shorting your power rail normally won't do that. Reversing is much worse but I've seen these parts even survive that for a short term.

Rick

January 02, 2012
by Rick_S
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Double check your contrast resistor also, it should be 1K (Brown Black Red ) It's hard to tell based on the photo, but if that's wrong, you won't get anything on your display.

January 02, 2012
by hevans
(NerdKits Staff)

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Hi Anirudha,

There is looks like there is something strange near your power wiring. There appears to be a wire connecting one of your crystal pins to either GND or +5. This would definitely cause the crystal to not operate correctly.

Humberto

January 02, 2012
by Anirudha
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Thanks for that Humberto. But I don't think I will get any different output anyways since the LCD is broken.

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